Methods and apparatus for supporting burst modes of camera operation

Abstract

In various embodiments a camera with multiple optical chains, e.g., camera modules, is controlled to operate in one of a variety of supported modes of operation. The modes include a non-motion mode, a motion mode, a normal burst mode and / or a reduced data burst mode. Motion mode is well suited for capturing an image including motion, e.g., moving object(s) with some modules being used to capture scene areas using a shorter exposure time than other modules and the captured images then being combined taking into consideration locations of motion. A reduced data burst mode is supported in some embodiments in which camera modules with different focal lengths capture images at different rates. While the camera modules of different focal length operate at different image capture rates in the reduced data burst mode, images are combined to support a desired composite image output rate, e.g., a desired frame rate.

Description

RELATED APPLICATIONS[0001]The present application claims the benefit of U.S. Provisional Application Ser. No. 62 / 065,534 filed Oct. 17, 2014 and U.S. Provisional Patent Application Ser. No. 62 / 242,911 filed Oct. 16, 2015 both of which are hereby expressly incorporated by reference in their entirety.BACKGROUND[0002]In an attempt to address some of the shortcomings of handheld camera devices, the use of a camera with multiple camera modules each of which may be used to capture an image has been suggested.[0003]Capturing subjects performing relatively higher speed actions is popularly known as the action shots. Examples of action shots are shots of sports scenes with motion, e.g., with individuals moving such as for example as part of a soccer game or other type of game, car race shots, etc. Such action shots are common in both consumer photography and professional photography e.g., sports photography.[0004]In the existing camera systems, action shots are typically captured by reducing...

AI Technical Summary

Benefits of technology

[0015]In at least some embodiments a motion mode of operation is supported. The motion, e.g., action shot, mode of operation is well suited for capturing scene areas where a portion of the scene area includes motion. In some embodiments during the motion mode of operation a camera module with a shorter focal length than at least one other camera module used to capture images is controlled to capture an image of a scene area using a first exposure time. The first exposure time maybe, and sometimes is determined from the content of a preview image without regard to motion. Thus, the first exposure time is well suited for capturing a large scene area even though portion of the scene area may include motion. During the motion mode of operation, camera modules with longer focal lengths capture portions of the scene area, e.g., because they correspond to a higher zoom level than the shorter focal length module. Whether a scene portion corresponds to motion or not is taken into consideration when determining the exposure time of the camera modules having the second, e.g., longer, focal length. If camera module corresponds to a scene portion with motion, the exposure time is selected to be lower than the exposure time of the camera module having the shorter focal length. However, if the camera module having the second longer focal length corresponds to a scene portion with no motion, the same exposure time used for the first camera module with the shorter focal length is used. However, in other embodiments, the exposure time for the camera module corresponding to the portion of the scene area without motion is determined independently based on the content of the scene portion to which the camera module corresponds without regard to motion when the camera module is determined to correspond to a scene portion without motion or with little motion. For camera modules with the second, e.g., longer, focal length which correspond to portions of a scene area with motion, an exposure time is used which is shorter than the exposure time used for the first camera module having the first, e.g., shorter, focal length. In this way, at least one image of scene area of interest will be captured with an exposure time optimized for the overall scene area while portion of the scene area with motion will be captured by a camera module or modules having a shorter exposure time which will reduce blurriness due to motion but potentially at the cost of using a less than optimal exposure time.

[0021]By controlling exposure times of different camera modules based on whether a camera module captures a scene portion corresponding to motion or not, and combining pixel values with pixel values from an image captured using an exposure time which was determined with regard to whether or not the scene included motion, the benefits of longer exposure times for static image portions and shorter exposure times for scene portions with motion can be achieved from images captured by a single camera device.

[0022]In at least some embodiments, a camera device including multiple camera modules supports a normal burst mode of operation. During the normal burst mode of operation each of a set of camera modules is operated in parallel during a number of successive image capture time periods corresponding to a period of time in which the camera operates in burst mode. The images from the camera modules are stored and then combined, e.g., to generate a composite image for each image capture time period. In such an embodiment since each camera module used for burst mode is operated during the individual image capture time periods, a large number of images are captured and stored. Such a mode can produce high quality images but can also require a large amount of memory to store the images captured during each capture time period as well as a fair amount of power to operate the full set of modules during each image capture time period.

[0023]In at least one embodiment, a camera device including multiple camera modules supports a reduced data burst mode. The reduced data burst can be provided as an alternative to the normal data burst mode or, in some embodiments the camera device allows the user to select between use of the normal burst mode and reduced data burst mode.

Problems solved by technology

This, in turn, increases the noise in the image given the reduction in light collection time and reduces the effective quality of the photograph generated using the reduced exposure time.

While memory costs have decreased, capturing large number of images, can still consume a large amount of memory particularly when an individual image is re-presented in using mega-pixels.

This problem is multiplied considerably when multiple camera modules are operated in parallel even for short periods of time during which a high image capture rate is used.

Furthermore, in addition to using large amounts of memory operating multiple camera modules in parallel can increase power requirements and drain a battery more quickly than if fewer camera modules were being used.

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